The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 1998
Filed:
Jun. 30, 1997
Marshall L Spector, Emmaus, PA (US);
Competitive Technologies of PA, Inc., Bethlehem, PA (US);
Abstract
An activated sludge process for reducing the amount of N.sub.2 O released to the atmosphere during biological oxidation of NH.sub.3, includes the following steps: mixing wastewater influent containing NH.sub.3 and BOD with activated sludge to provide a mixed liquor in a first enclosed aerobic treatment zone wherein an oxygen containing gas is introduced, the first enclosed aerobic treatment zone having two or more stages in which gas and liquor phases are staged and oxygen is transferred to the liquid phase and BOD is metabolized and NH.sub.3 is oxidized to NOx and N.sub.2 O, wherein the pN.sub.2 O is maintained at a level greater than 2 mm Hg; transferring the mixed liquor and gas to a second enclosed treatment zone having two or more stages, in which gas and liquid phases are staged, and wherein NOx and N.sub.2 O are reduced to N.sub.2 and an effluent gas is released to the atmosphere; transferring the mixed liquor to a settling zone wherein the activated sludge is separated from the mixed liquor to form a dense sludge and a clear supernatant; and returning at least a portion of the dense sludge to the enclosed aerobic treatment zone.